Variable
|
Categories
|
Case group (N = 507)
|
Control group (N = 520)
|
p-value
|
---|
Number
|
Percent
|
Number
|
Percent
|
---|
H1N1 infection
|
No
|
462
|
91.1
|
490
|
2.0
|
< 0.001a
|
Yes
|
44
|
8.7
|
10
|
2.0
|
H1N1 vaccine
|
No
|
488
|
96.3
|
495
|
97.4
|
0.212a
|
Yes
|
18
|
3.6
|
13
|
2.6
|
Travel
|
No
|
470
|
92.7
|
370
|
69.7
|
0.059a
|
Yes
|
36
|
7.1
|
24
|
4.5
|
Social distancing
|
No
|
397
|
78.3
|
267
|
67.8
|
0.256a
|
Yes
|
109
|
21.5
|
127
|
32.2
|
Close contact
|
No
|
475
|
93.7
|
358
|
91.8
|
0.979a
|
Yes
|
31
|
6.1
|
32
|
8.2
|
COVID-19 infection
|
No
|
490
|
96.6
|
515
|
97
|
0.942a
|
Yes
|
16
|
3.2
|
16
|
3
|
symptoms
|
None
|
479
|
94.5
|
508
|
95.7
|
< 0.001a
|
Fever
|
0
|
0
|
8
|
1.6
|
0.004b
|
Sore throat
|
7
|
1.4
|
6
|
1.2
|
0.745a
|
Nasal congestion
|
8
|
1.6
|
2
|
0.4
|
0.050a
|
Cough
|
7
|
1.4
|
6
|
1.2
|
0.747a
|
Shortness of breath
|
8
|
1.6
|
6
|
1.2
|
0.558a
|
Headache
|
4
|
0.8
|
3
|
0.6
|
0.486a
|
Weakness and muscle pain
|
5
|
1.0
|
13
|
2.6
|
0.094a
|
Reduced sense of smell and/or taste
|
9
|
1.8
|
7
|
1.4
|
0.622a
|
Ocular problems
|
4
|
0.8
|
1
|
0.2
|
0.179b
|
Other
|
11
|
2.2
|
0
|
0
|
< 0.001b
|
Screening
|
No
|
477
|
94.1
|
476
|
89.6
|
0.137a
|
Yes
|
29
|
5.7
|
42
|
7.9
|
Admission
|
No
|
505
|
99.6
|
520
|
100
|
0.494b
|
Yes
|
1
|
0.2
|
0
|
0
|
Isolation
|
No
|
493
|
97.2
|
420
|
97.2
|
0.790a
|
Yes
|
13
|
2.6
|
12
|
2.8
|
- Results of: aChi square test, bFisher’s exact test